Desertificaton

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    Today, the earth’s deserts are spreading and getting larger and desertification is a serious problem facing the world. The major reason for this is irresponsible cutting down of trees. As is shown in the first cartoon, when people cut down trees desert forces on and becomes irrepressible.

    People cut down trees for various reasons but the may forget that tree play a vital part in water and soil conservation. Trees can preserve moisture and fertility in the soil, protect soil against erosion and prevent fertile land from becoming desert. Therefore when people cut down all of the trees, the earth lies bare and dry in the host sun, and desert is inevitable.

    Desertification can lead to many other serious problems which may threaten the existence of human beings such as a reduction of arable land, terrible drought and famine. In order to prevent desertification, people have to plant trees, as the second cartoon shows. The time when people plant trees is the time when desert retreats. People should not cut down trees and more, as is done in the first cartoon, but rather, they should plant more trees, and only in this way can desertification be finally defeated.